The OEX Leviathan EV 900 also comes with a stuff sack and a storage bag that allows the bag to stay lofted when you’re not using it for any extended periods of time.

Very warm despite its low weight and bulk, the OEX Leviathan EV Hydrodown 900 Sleeping Bag is ideal for temperatures around -9°C, but will keep you comfortable down to -16°C. I then spent half the night trying to fix the zip but to no avail so I wouldn't freeze to death in the sub 4 degrees Celsius weather. Also the zip often snagged which was frustrating when trying to get back inside quickly after a toilet visit. You need fewer feathers the higher the fill power, so down products made with down of a higher fill power (750 or 900) will normally be lighter, more packable and pricier as a result. It comes with a host of premium features like insulated baffles and ultra-comfort lining for a great night’s sleep.It has been designed and developed in the UK by camping experts and comes with a host of practical features that make it a superb choice for regular campers. If you use the provided stuff sack, you can get it down to the size of a watermelon or a standard football, and weighing just over 1.

You can comfortably carry it for miles on winter hikes, and you could even extend its use to winter bikepacking or fastpacking trips if you had enough room in your set-up. But after three years and over 50 nights in it, the bag hasn’t lost any of its warmth or loft whatsoever.

After years of messing about I now use a two bag system that together weighs 1080g and can handle -8deg. The zip is also lined with a thick strip of protective material, which minimises snags and ensures you don’t accidentally tear the soft inner while zipping the bag up.

the Leviathan EV 900 is also reasonably lightweight considering the temperatures this thing is built for. As he got older, the hills got bigger, and his passion for spending quality time in the great outdoors only grew - falling in love with wild camping, long-distance hiking, bikepacking and fastpacking. I’ve always been impressed by its performance, be that on a rainy thru-hike of Germany’s Black Forest National Park, dozens of winter nights in and around Snowdonia’s Glyderau, or 10 chilly October nights in Wyoming’s Grand Teton National Park.

I’m certain you’ll be alright in a standard Rab Ascent length at 6’1”as that’s within their recommendation. As one of our expert campers, Craig revels in testing camping equipment and knows a sturdy shelter from on that will give up the ghost when conditions become challenging. When used on the move, it packs downs well ( to roughly the same size as a standard football) and lofts back up in no time at all (especially if you fluff it up as you toss it into your tent).

They tested the bag according to EN13537 (which is an industry standard means of testing how warm sleeping bags are), and having used the bag for over three years, we definitely have some thoughts on these numbers (which we cover below). Overall this is a decent bag for the money and if you remember that it is a budget bag you will be okay.My advice would be to get a Rab Ascent 500 or possibly 300 for spring/summer/autumn and supplement it with a cheap summer bag for winter. I should point out most camping will be March - October in and around the UK, not really planning on summit camps at the top of Ben Nevis or Snowdon etc. I’ve had the OEX Leviathan EV 900 for a few years now, and I’ve slept in it at varying temperatures in different climates.